Imagesetter

Abstract

Imaging apparatus is provided which includes a generally cylindrical support defining a substrate support surface, a head operative to record information onto a substrate on the substrate support surfaces, and apparatus for precise rotational positioning and displacement of the cylindrical drum with respect to the imaging head. The apparatus includes at least one linear motor arranged to drive the cylindrical support in rotational motion, and control apparatus for providing electrical inputs to the linear motor to achieve precise rotational positioning of the substrate support surface.

We claim: 
     
       1. Apparatus for imaging a substrate mounted on a drum, said drum having a longitudinal axis, said drum having a surface which is uniform, non-uniform or combinations thereof said apparatus comprising: an imaging head for recording information onto said substrate; and   apparatus for precise rotational positioning and axial displacement of said drum with respect to said imaging head including: at least one linear motor in operative communication with said drum; and   a controller in operative communication with said at least one linear motor apparatus and said imaging head, for synchronizing the rotational and axial positioning of said drum with said imaging head.     
     
     
       2. Imaging apparatus according to claim 1 and wherein said substrate is supported externally by said drum. 
     
     
       3. Imaging apparatus according to claim 1 and wherein said linear motor operatively engages said substrate. 
     
     
       4. Imaging apparatus according to claim 1 and wherein said drum also defines at least one flange and wherein said linear motor operatively engages said at least one flange. 
     
     
       5. Imaging apparatus according to claim 1 and wherein said drum also defines at least one end portion and wherein said linear motor operatively engages said at least one end portion. 
     
     
       6. Imaging apparatus according to claim 1 and wherein said drum is fixedly mounted on a shaft and wherein said linear motor operatively engages said shaft. 
     
     
       7. Apparatus according to claim 1 and wherein said linear motor operatively engages said drum. 
     
     
       8. Apparatus according to claim 1 and wherein said linear motor is a ceramic linear motor. 
     
     
       9. Apparatus according to claim 8 wherein said linear motor is a very high precision ceramic linear motor. 
     
     
       10. An imagesetter for imaging a substrate mounted on the surface of a substrate support surface, said substrate support surface having a longitudinal axis, said substrate support surface having a surface which is uniform, non-uniform or combinations thereof, said imagesetter comprising: a plotting head for transferring information to said substrate; and   a substrate feed and positioning assembly for supplying, feeding, axial positioning and removing said substrate comprising: a plurality of linear motors in operative communication with said substrate; and   a controller in operative communication-with said plurality of linear motors and said imaging head for synchronizing the feeding and axial positioning of said substrate with respect to said plotting head.     
     
     
       11. Apparatus according to claim 10 wherein said plurality of linear motors is arranged in multiple juxtaposed pairs which are operative to displace a substrate interposed therebetween.